Receive the latest national-international updates in your inbox

Seven people, including the ex-husband of a former "Sopranos" star, have been charged by federal authorities with conducting a $300 million dollar stock fraud scheme involving four publicly traded companies, prosecutors say.

FBI agents made arrests Thursday in New York and several other states on charges including securities fraud, mail fraud and wire fraud, law enforcement officials said.

Top Celeb Pics: "Woman in Gold" Premiere

One of the defendants named in the 10-count federal indictment is Abraxas Discala, ex-husband of actress Jamie-Lynn Sigler, who played the role of Meadow Soprano on the HBO television series "The Sopranos."

Discala is the CEO of OmniView Capital Advisors and lives in Connecticut. His attorney, Joseph Tacopina, said, "Anyone who knows A.J. is shocked by these allegations. And that is exactly what they are -- merely allegations. He will vigorously defend these charges."

Law enforcement sources describe the fraud allegedly run by the defendants as a “pump and dump” scheme involving penny stocks in which stock manipulators buy large quantities of stock, artificially inflate the price by making misleading statements and then sell the stock at a higher price.

According to the indictment, the defendants allegedly manipulated the stock of four companies by issuing false and misleading press releases, making false filings to the Securities Exchange Commission, concealing their ownership interests and making unauthorized purchases of stock in the accounts of unwitting investors. They also allegedly engineered price movements and traded volume in the stocks.

In a statement, Brooklyn U.S. Attorney Loretta Lynch said the defendants "took companies with essentially no assets or activity and deceived the market into believing they were worth hundreds of millions of dollars through a dizzying round of insider and unauthorized trades."

"This lucrative scheme to manipulate our financial markets made the defendants money while draining the bank accounts of innocent investors," added Assistant FBI Director George Venizelos. "Their client-victims trusted them to manage their money as if it were their own, not to steal it."